A watchdog body had no legal power to publish its findings of police collusion with loyalists who massacred six Catholic men nearly 23 years ago, the High Court heard.

Lawyers for two retired senior officers claimed the Police Ombudsman report into the Loughinisland atrocity should only have been released if it recommended prosecutions or disciplinary action, a hearing in Belfast heard on Thursday.

Raymond White and Thomas Hawthorne are seeking an order to have the findings quashed.

UVF gunmen opened fire at the Heights Bar in Loughinisland, Do Down as their victims were watching a World Cup match in June 1994.

In June last year the Police Ombudsman, Dr Michael Maguire, said collusion was a significant feature in the murders.

He found no evidence police had prior knowledge of the attack, but identified "catastrophic failings" in the investigation.

One of the suspects in the attack was an informer, according to the findings.

Police were also said to have been aware of a UVF gang operating in south Down and involved in previous murders.

Other failures identified in the report included a delay in arresting suspects whose names were known within 24 hours of the shooting.

But Mr White, a representative of the Northern Ireland Retired Police Officers' Association, and Mr Hawthorne, a retired chief superintendent and former sub-divisional commander in the area, are now challenging the legality of the document.

Counsel for the pair, David McMillen QC, set out two statutory outcomes to any Police Ombudsman investigation triggered by a complaint: either recommendations to the Director of Public Prosecutions or referring the case to the Chief Constable for disciplinary proceedings.

He argued that the watchdog has no general power to produce a report or come to a final determination outside that remit.

During exchanges Mr Justice Maguire said it seemed astonishing to suggest the Ombudsman must close the files if neither outcome is reached.

The barrister insisted, however: "What a public statement may not do is put the Police Ombudsman in the position of the person who comes to a final determination."

He added: "What he cannot simply do is say I want to investigate the police response to the Loughinisland atrocity in general terms and produce a public report as my outcome.

"All the implications are that the primary purpose of the Police Ombudsman is carrying out what he believes was a public inquiry into the atrocity.

"We simply say he's not permitted to do that."

Responding on behalf of Dr Maguire's office, David Scoffield QC, described the legal action as an attempt to significantly restrict the scope of the Ombudsman's investigations.

He insisted that his client has broad powers to operate under.

"Were he to simply act as a filter for criminal prosecutions or disciplinary proceedings that would essentially neuter his office in any case where those results, for whatever reasons, were not possible," Mr Scoffield said.

Reserving judgment in the application for leave to seek a judicial review, Mr Justice Maguire pledged to give his decision as soon as possible.

Outside court Emma Rogan, whose father Adrian was among those killed in the massacre, spoke of her continued anguish.

She said: "I feel this application itself has a re-traumatising affect. The report was accepted by the Chief Condstable and two successive Prime Ministers."